Taps like the Nukatap have a 3/8 Inch UNC-16 thread for their tap handles. This seems to be quite common outside of germany. But many tap handles here in germany have a M10 thread. This is just a simple adapter to screw german tap handles on non german taps. This should let you use the nice promotional tap handles from german breweries on your Kegland Nukataps etc.
The author hasn't provided the model origin yet.